Puppet

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Puppet

https://puppet.com/

https://forge.puppet.com/ <-- Where to get Modules

Puppet code is a declarative language, which means that you describe only the desired state for your systems, not the steps needed to get there

One of Puppet's core concepts is the resource abstraction layer. For Puppet, each aspect of the system you want to manage (such as a user, file, service, or package) is represented in code as a unit called a resource. The puppet resource tool lets you view and modify these resources directly.

Puppet Master --> [Catalog] --> Node --> [Facts] --> Puppet Master

  • Facts = data about its state
  • Catalog = Facts are used to compile a catalog that specifies how the node should be configured


Puppet agent uses providers to check for difference between current and desired state. The Providers help puppet implement whatever changes are necessary

Types

See what Puppet knows about a resource

sudo puppet resource file /tmp/
file { '/tmp/':
  ensure => 'directory',
  ctime  => '2020-03-28 19:15:40 +0000',
  group  => 0,
  mode   => '1777',
  mtime  => '2020-03-28 19:15:40 +0000',
  owner  => 0,
  type   => 'directory',
}

sudo puppet resource package httpd ensure=present Installs a package using the default package manager

Manifests – puppet code saves as .pp

Run a manifest directly (without puppet master involvement)

sudo puppet apply /tmp/hello.pp 

Class – named block of Puppet Code – Class brings together resoures that manage one logical component of a system

Module – directory structure


Template Files

Not required, but nice to have, an initial block that shows what variables are expected to be passed into the template

<%- | $port,
      $default_character,
      $default_message,
| -%>
# This file is managed by Puppet. Please do not make manual changes.
---
:default_character: <%= $default_character %>
:default_message:   <%= $default_message %>
:sinatra_settings:
  :port: <%= $port %>

Simple Validator

puppet parser validate pasture/manifests/init.pp


Normally to update the host (instead of waiting for the timer)

sudo puppet agent --test

Run and make no changes

sudo puppet agent -t --noop


Relationship metaparameters tell Puppet about ordering relationships among your resources.

  • before => File['/etc/pasture_config.yaml'], <-- create my resource before this other resource (config file) is generated
  • notify => Service['pasture'], </code) <- on change tell this other resource

When a host stops reporting, it will not fetch anything


Manifests

Using the default parameters

include module_class

Passing in parameters

  class { 'pasture':
    default_character => 'cow',
  }

puppet encrypt

ssh-keygen -f hostname -C hostname -t ed25519
sudo /opt/puppetlabs/puppet/bin/eyaml encrypt -f hostname

Forman Integration

If the branch that the environment is using gets merged/deleted the nodes stop updating as puppet cant find a class = branch. puppet only needs to find a branch thats 'alive' then it will get told the right information from forman. so

sudo puppet agent -t --environment develop

Instead of --->

Usually when someone has stopped puppet - done lots of changes, potentially deleted the branch it was configured with.

Ensure that the /etc/puppetlabs/puppetpuppet.conf files environment is correct

[main]
vardir = /opt/puppetlabs/puppet/cache
logdir = /var/log/puppetlabs/puppet
rundir = /var/run/puppetlabs
ssldir = /etc/puppetlabs/puppet/ssl

[agent]
pluginsync      = true
report          = true
ignoreschedules = true
ca_server       = puppetmaster.domain
certname        = thishost.domain
environment     = develop
server          = puppetmaster.domain
splay = true